It was about 3 p.m. Monday when the line of expected thunderstorms began moving into Terry Ritter's territory - A 75-mile area of southeastern Virginia stretching along the North Carolina border from Norfolk to Emporia.

"It was moving southeast and we had some very high (cloud) peaks showing up on the radar near Emporia," said Ritter, chief meteorologist with the U.S. Weather Service here.

"We were watching them, and put out severe storm warnings for that area, but about 3:30 they still seemed about an hour away from us. Then the line of storms suddenly began forming along the eastern end of the front, moving very fast and we were startled by a hook echo on the radar (indicating a probable tornado) over Suffolk, just 16 miles away."

At 4 p.m. the storm struck Norfolk with unprecedented speed and fury, drowning at least four people, leaving nine others missing, ripping roofs from buildings and smashing car windows.

Its 98 m.p.h. winds and golfball-sized hail splintered trees (more than 200 in Norfolk alone) and street signs and knocked out electric power to more than 100,000 homes in five Tidewater cities. A lightning bolt from the storm struck and critically injured a 14-year-old girl in Virginia Beach.

A storm-spawned 15-foot wave slammed into a 43-foot charter fishing boat, capsizing and drowning four persons before they could even reach for life preservers.

Sixty minutes after it struck, the storm was over.

Coast Guard and Navy rescue teams in helicopters and boats and Tidewater-area residents today searched for several miles in the vicinity where the fishing charter Dixie Lee II capsized. But there was no sign of nine missing people. Fourteen were rescued by another fishing boat.

Monday's storm, although more severe than most, was no insolated phenomenon, but a regular seasonal product of the Chesapeake Bay, according to Ritter and other meteorologists familiar with the area.

"This is a very dangerous place for thunderstorms," said Ritter, who was transferred here about five years ago from Ohio. "I've seen far worse tornadoes in the Midwest than we ever see here. Here a tornado may take your roof but it probably won't take your house.

"But I've never seen more sewere thunderstorms than we get here, with such severe winds."

Ritter said thunderstorms can be caused by one or more of several factors, including large columns of heated air rising from a sun-baked land mass; huge areas of water vapor evaporating from a body of water, and converging weather patterns such as a sea breeze and a land breeze - all of which can produce towering clouds and unstable air aloft.

The large land area around the Chesapeake Bay gets a hot summer climate and its proximity to the ocean combine all three of these factors, he said, producing storms of unusual speed and intensity that may be quite localized in scope.

Yesterday he said, in addition to those factors, "we had an unusually intense, high-altitude low-pressure trough moving in on us from Canada, bringing temperatures as much as 20 degrees cooler than those on the surface."

The result, he said, was extreme instability along the face of the front, with hot air updrafts butting against cool air downdrafts - a condition he compared meteorologically to a pot of boiling water.